As related-art documents that disclose a configuration of a movable front spoiler device, there are WO 2015/191697A (Reference 1) and JP 06-227444A (Reference 2).
An active front deflector described in Reference 1 includes a deflector, a link mechanism, and an actuator. The actuator includes a deceleration mechanism unit. Due to the deceleration mechanism unit, the actuator is difficult to rotate in reverse. The actuator has a clutch structure in which driving transmission is disconnected upon receiving a load exceeding a threshold. In the clutch structure, engaging surfaces of teeth engaged with each other are inclined surfaces, and when teeth at one side ride on the inclined surfaces of the teeth at the other side, the engagement between the teeth is released and driving transmission is disconnected.
A front spoiler device described in Reference 2 includes a spoiler, a frame, an arm, a link, and an actuator. The link has an elastically deformable perforated structure.
The active front deflector described in Reference 1 is configured such that the engagement between the teeth is released by bringing the inclined surfaces of the teeth into sliding contact with each other. However, the frictional resistance between the inclined surfaces vary due to factors such as, for example, the outside air temperature or adhesion of dust to the inclined surfaces, so that the threshold of the load varies when driving transmission is disconnected. As a result, an overload may act on the deflector, thereby causing damage to the deflector.
In the front spoiler device described in Reference 2, the load acting on the spoiler is reduced by elastically deforming the link, but it is necessary to secure both the amount of elastic deformation of the link and the rigidity of the link. Therefore, when it is impossible to secure a sufficient amount of elastic deformation of the spoiler, an overload may act on the spoiler, thereby causing damage to the spoiler.
Thus, a need exists for a movable front spoiler device which is not susceptible to the drawback mentioned above.